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Whats the deal with the array of 1720 conversions available on the market? I've an engine that has suffered through being stored for too long without proper attention (failed its MOT and then wasnt driven for 5 years till I bought it) but I'm still alarmed at the appauling state of wear to the cylinders given that its only covered 4500 miles since the engine rebuild It was fitted with a shasta set in 1999 but I'm put off buying these again for this reason (and the price!). Vendors of such parts though seem a bit candid about giving any details about what they sell Performance Products sell a Japanese alternative but thats all the details they give (no mention of whether they're cast or forged) and Roger Bray said if I part with £1000 I can have a set reccommended by a top European specialist that are better for road use than shasta due to being a forged piston and a tighter fit in the bore (material exhibits less thermal expansion than the alloy used in the shasta kit) but they wont tell me who makes them or which famous european 356 expert reccommended them in the first place (presumably incase I try to go buy them direct perhaps).
Camshafts too. The only decent source of info I can find on these is web cam....no one else seems to publish their specs for comparison?
Cant find anywhere to order literature either........all HCPs books seem to be out of print and although I have Duane Spencers 912 guide it seems a little brief and out of date in terms of describing whats available on the piston and cylinder market......not to mention biased?
So how do I break into this circle of secrecy surrounding the re-build of my 912 engine?
My 12 is running with NPR pistons in it - but as far as I am aware these kits haven't been available for a long time although these don't have the greatest reputation for longevity and quality...must confess to not having heard of many people with bad experiences of Shasta products - isn't Andy Prill the UK agent?
My engine is relatively stock other than 1720cc pistons - It wasn't built with too high a compression, but it goes pretty well for a little car
I have a set of Shasta pistons waiting to be built into a spare engine when time etc permits.
1966 912 Karmann Coupe - polo red.
1972 914/6 GT replica - 2.7 - signal orange.
1961 Standard 217 Tractor.
2003 Boxster S.
1967 Alfa Giulia Sprint GT Veloce.
Thanks for the input.........I've already got a cal look bug and a box of bits for an 82x94 motor which was next on the list after the 912 clutch change
I want to keep the 912 porsche powered and to this end if I was going to give up on the super 90 would be tempted to try and slap a 3.0sc engine in and modify the suspension and brakes to suit ..........something tells me that fixing the 4-pot will still be cheaper though so not quite the excuse I need yet
Indeed AJP is the UK agent but they were bought so long ago and with the issue of the engine not being stored correctly I dont think I'd have a case for a warranty claim. I do have a receipt but only way I can prove the mileage is with relevant MOTs too. I was however going to ring to ask if he could supply a set of barrels only.......depends on how closely they ought to be matched to the pistons I guess
With out going into too much detail ( Miggs knows why ) Dauane and I are NOT best buddies and that's what I am going to say on the matter......
His book is nice and full of pictures and that's about it , There is some good info but what bit is good and what is not well that's the killer question.. Still worth a read it's a good book for newbie owners to read and learn some of the rules of the car what's not and what's good...
Engine rebuilds for 912's
right there is only one way to do this and the right way...
I have done HUGE amounts of home work on this and I am still learning now...and I always will.
There is no doubt about it 912 enignes are F**** expensive to rebuild but that's life and save your cash your going to need it... The end result is worth it and a pleaseure to drive.
P/C sets there has been a number over the years good and bad but at the moment the Shasta's are the best on the open market and although I thought the new sets that are about where ment to be better ( cylinder ) it seams I am wrong and that the best are the Cast iron ones ( the same as the ones I sold you Ian ) These are good units and wear well and are stable when HOT...Old Cast iron.
4500 miles of ware hmmm shouldn't do as Andy has some that have been in a race engine done some VERY hard miles and a high mileage engine at that and it's still as good as new..
If you can get the bores rehomed then use them new rings and your away.
Spend your money on the crank I am going though this now A regrind if needed is about £100-140 and get it tested I have done a lot of asking around and looking into the need for rehardening and on the most I have had more mix responce on this issue I would now NOT reharden the crank as it's much much more of an issue about keeping it true during the heat treatment.. so leave alone Harry Pellow did a test on a crank to see how deep the heat treatment Porsche had done form orginal and it was DEEP so no reason to do it again..
Clean the crank well again I had mixed responce to weather to drill and replug the crank I am more worried about this than any other part of the crank operation because I know if not done by a very skilled craftsman your engine is going to be buggered VERY quickly if it comes out..
Crank regrinds to be honest I phoned around and I sent it to Andy At APJ he knows his stuff and so does the crank grinder he uses as Andy has a set up with him so it works.. don't reinvent the wheel.
Cams well again more research I want to keep the Solex's I like them... so I want to increase the performance so I have to look for a cam that covers all the above and New Tec was a crank that came back from a number of people and again as Andy sells them I am getting one from him. Only as he is doing the crank at the same time..
I have a local firm to do the heads as they are old school and very good
keeping your P/C set and getting a crank reground and new bearings be very quick and BUY the old style bearings as the new ones being sold are hmmmm lets say crap but in time we will have no choice but to use them so then they will be still crap but less crap ...they are metal backed weigh twice as much and will need an expert eye to fit them out with the files... some thing alot of builders have NEVER had to do with the orginal bearings...so be warned.......
so for £1000-1500 you could have a very good bottom end and a cam worth running about another £500 more and you could have a good set of heads so you are looking at £2000 or just under that's what I am up to so just go to live it and get it sorted..
The most likely source of the Good Pistons is Mahle in fact:
I do know Eric Studer can get them readily..he is alos an excellent source of advice generally..
The hardening will not survive a normal grind I'm afraid.
The purpose of the hradening is to induce compressive stress into the surface to delay fatigue cracking.
Which we all know is a major issue on the 912 crank..in contrats to the early 9111 for example..
There are places which can grind and harden and strighten and regrind correctly..
There is an alternative source of the Good Pistons which we are dealing with at present..on 911 pistons..they are not especially fast , but are very throrough.
A four- piston set from these guys will be costly..about 800 pounds.
Less for a few sets of course..any other takers?
Let me know if you want me to investiaget for you..
Based on a 'spare' S90 engine and rebuilt over the last year on my bench it's now ready to bolt together for the last time before it goes in the car this winter.
Sorry not been ignoring this....just got back from a long weekend trip to VW autostadt amongst other things
I've seen the LN engineeering stuff before and must admit on paper it looks like the best engineered product there is out there for upgrading a 356/912 engine (never understood why no one wanted to go bigger than 1720 before!) but I'm afraid its just too much dollar for me
After a consultation with AJP I've decided to re-use the shasta pistons and get some new "durabar" cylinders and an SX1 cam (probably) and we'll see how it goes on that set up. Best compromise on price and reliability within my grasp I felt.
It was fitted with a shasta set in 1999 but I'm put off buying these again for this reason (and the price!). Vendors of such parts though seem a bit candid about giving any details about what they sell Performance Products sell a Japanese alternative but thats all the details they give (no mention of whether they're cast or forged) and Roger Bray said if I part with £1000 I can have a set reccommended by a top European specialist that are better for road use than shasta due to being a forged piston and a tighter fit in the bore (material exhibits less thermal expansion than the alloy used in the shasta kit) but they wont tell me who makes them or which famous european 356 expert reccommended them in the first place (presumably incase I try to go buy them direct perhaps).
..........something tells me that fixing the 4-pot will still be cheaper though so not quite the excuse I need yet 
